Hedlund 980cc V-Twin
Around 40 V-Twin engines were also built.
The Swedish Hedlund motor, built between 1967 - 1968 and was a DOHC engine. The Hedlund was tested by Bengt Jansson who also ordered Alf Hagon to build for him a special grasstrack machine, with the Hedlund engine installed.
Throughout the Workshop pages, you can find many different types of valve systems that include OHV, SOHC and DOHC, and in combinations that include 2V, 3V, 4V and even 5 valves.
However, there are (as far as we know), only 4 engines that incorporate a DOHC system in
combination with a 2Valve set up. These are:
The MSM from Australia
The old JAWA iceracer DOHC 2V
The EICOH from Japan
The HEDLUND from Sweden.
There is another engine with the same layout (DOHC 2V) but this engine is used only for iceracing and it is the SIWA made in Austria by the Wartblichter Brothers - hopefully some information on this one will be forthcoming.
Further just for your information DOHC system are made in 2 types, - (A+B)
By the type A the cam lobes are operating the valves directly by tappets.
By the type B the valves are operated by normal valve rocker arms.
Both the EICOH and HEDLUND are of the type B.
In the head, both cams are connected by gears, but the inlet camshaft is also chain driven from the crankshaft. The small Stefa magneto is mounted at the end of the exhaust cam. All moving parts in the head run at high quality needle bearings. Also very interesting, is the fact that the HEDLUND is a unit construction, (like the Maely) and the total weight of the engine including the clutch and layshaft is only 35 Kg.
The crankcase is made of elektron, and because this is very corrosive, the crankcase is protected by a gold coloured Eloxal. For speedway there is only a simple layshaft mounted in the unit but for grasstrack racing there is the possibility to fit a 2 speeder.
Bore x Stroke
= 99 x 80 mm
Power? = 50 Bhp @ 6500 Rpm
Carburettor = Dell'Orto
Clutch = Norton
The Hedlund Story ... here
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